The deleterious effects of global climate change, increasing the earth's average temperature, are increasingly obvious. These effects, which are likely to increase in magnitude over the foreseeable future, include an increase in sea level, a reduction in the percentage of the earth's surface covered by the polar ice caps, changes in rainfall distribution, increases in the severity of storms, and changes to oceanic currents. Diverse and profound changes in the distribution of habitable land areas for various species, as well as in the distribution of areas suited to agriculture, and changes in locations of usable coastal ports and shipping routes may well follow. Even if the production of greenhouse gases were to be sharply curtailed in the near future, the effects due simply to the already significantly reduced area of the polar ice caps are likely to be serious, and efforts to preserve, protect or even rebuild the ice at those locations are highly desirable.
A positive feedback loop known as the Ice-Albedo Feedback Effect is involved in the reduction of icecap area, whereby the more the ice melts, the faster the remaining ice melts. This occurs because for a given area, the open ocean absorbs more solar energy (has a lower albedo) than does ice. Moreover, newly formed ice, formed over the course of a single winter, typically is less reflective (has a lower albedo) than ice that has remained frozen through one or more years. Because of global warming, more of the increasingly scarce multi-year (high albedo) ice melts each summer, and even though substantial first-year ice is generally formed in the following winter, the overall change over the past 3 decades has been a continued drop in the effective overall albedo of the polar icecap.
It is therefore desirable to provide ice of high albedo to the regions of interest, breaking the positive Ice-Albedo feedback loop and helping to restore the polar icecaps to the point that they can increasingly resume their function as the earth's “natural refrigerator”.
It may also be desirable to provide ice with modified thermal properties, that may be independent of albedo, but that nevertheless serve to encourage the formation or persistence of other ice in the vicinity of the provided ice, and thus indirectly contribute to the goal of increasing the effective albedo of the local region.